Tube flaring machine



June 21, 1960 J. B. oTTi-:sTAD ETAL 2,941,568

TUBE FLARING MACHINE 2 Sheets-Sheet l Filed April 2l, 1958 Nw www. .A SH @N Nm. Nwx mm .NN wm Lem wm El NN SQQ I msx L. LUI. m

June 21, 1960 J. a. oTTEsTAD ETAL 2,941,568

TUBE FLARING MACHINE Filed April 21, 1958 2 Sheets-Sheet 2 f MIG: 105 6 ,TMre-MRS Cha-z :BE/wav rresmn, SAMUEL. A'Qrf/u/z SMEs/4 TUBE FLARING MACHINE Jack B. Gttestad, Claremont, and Samuel A. Skeen, West Covina, Calif., assignors to General Dynamics Corporation, San Diego, Calif., a corporation of Delaware Filed Apr. 21, 1958, Sex'. No. 729,987

8 Claims. (Cl. 153-79) This invention relates generally to apparatus for shaping the end portions of tubes; more particularly, it relates to apparatus which utilizes fluid pressure for such shaping.

Shaping of the end portions of tubes has conventionally been accomplished by means which involve the urging of a spinning mandrel, a spool or various types of tools against a tube end portion while the tube is clamped. This general method is characterized bycertain disadvantages, including that of requiring a relatively long forming time. This has caused work hardening and stress concentrations in certain materials and has therefore resulted in tube damage during shaping operations and tube failures in service.

The present invention utilizes fluid pressure for shaping the end portions of tubes. It is capable of applying shaping pressure to a tube at a high optimum rate which substantially eliminates such problems as those resulting from work hardening and stress concentration. The shaping pressure itself operates means for retaining the shaping pressure within a tube during the shaping operation.

VFor rapidly producing a shaping pressure and for predetermining its rate of application to a tube, a preferred embodiment of the present invention utilizes features of the pressure generator described and claimed in the copending application of Jack Benton Ottestad and Samuel Arthur Skeen, Serial No. 709,992, filed January 20, 1958. The input pressures utilized in the pressure generator are also utilized with the present invention toactuate mechanisms for clamping a tube upon the application of the shaping pressure and for unclamping the' tube upon the relieving of that pressure.

It is therefore an object of the present invention to provide a novel apparatus which utilizes uid pressure for `shaping the end portion of a tube.

` An object of this invention is the provision of a novel tube shaping apparatus which is adapted for shaping material at an optimum high rate which minimizes work hardening and stress concentration.

It is an object of this invention to provide a novel `device for economically and conveniently shaping the end United States atentfj() ice 2,941,568 Patented `lune 21, 19.60

Figure l is an elevational view, partially in section, of a preferred embodiment of the tube shaping apparatus of the present invention mounted in operative relation with a control panel;

Figurel 2 is an elevational sectional view showing a portion of the apparatus of Figure 1 on an enlarged scale;

Figure 3 is a fragmentary sectional View showing a portion of the apparatus of Figure 2 on an enlarged scale with certain elements in different operating positions;

Figure 4 is a perspective view showing a tool ring and a clamping cone utilized with the present invention;

Figure 5 is a perspective view showing the elements of Figure 4 with their respective parts radially expanded from the contracted conguration shown in Figure 4; and

Figures 6 and 7 are fragmentary sectional views showing modified forms of a seal member and a tool ring utilized with the present invention in dilferent positions during a tube anging operation.

Referring to the drawings, and particularly to Figures l and 2, there is shown a preferred embodiment of the tube-flaring machine of the present invention. Cylindrical vsections l0, 12 and 14, an actuator end wall 16 and an end member 18 constitute a machine housing. An orifice plate 20 is disposed between cylindrical sections 10 and 12, and an annular wall member 22 is similarly disposed between cylindrical sections 12 and 14. Peripheral flange portions of the plate and wall member abut the ends of respective cylindrical sections, as shown. Reduced portion 24 of the actuator end wall and reduced portion 26 of the end member accommodate end portions of cylindrical sections 16 and 14 respectively, as shown in Figure l. The cylindrical sections, the actuator end wall 16, orifice plate 2t), the annular Wall member and the end member are secured in clamped relation by tie bolts 2S, which extend through registering apertures spaced symmetrically about end member 18 and actuator end wall 16. Pressure sealing is provided between each cylindrical section and the parts adjacent thereto by annular sealing eleto actuate means for clamping and unclamping a tube.

Other objects and features of the present invention, as well as many advantages thereof, will become apparent to those skilled in the art from a consideration of the following description, the appended claims and the accompanying drawings, in which:

ments 3G disposed in appropriate grooves.

The tie bolts and nuts 32 secure one end of the tubearing machine to a mounting wall 34 which rests on a base 36. The other end of the machine is seated in an arcuate portion (not shown) of a support 38 mounted on the base. A control panel 4d (shown in phantom outline) is connected with the tube-flaring machine in conventional manner and affords convenience of operation. It is provided with appropriate couplings, indicators and controls, including a control handle 42.

The machine housing contains a pressure generator and a tube-Haring apparatus. Referring to Figure l, the pressure generator includes an actuator piston 44 slidably positioned Within cylindrical section 12 and secured to a thrust column 46 by engagement of its threaded axial opening with a reduced threaded end portion of the thrust column. Pressure sealing between the piston and the cylindrical section is provided by a seal ring 48 carried in a peripheral groove in the piston. An orifice 5t) is defined in the orifice plate and an annular seal plate 52 is secured thereabout, as by screws 54, in confronting relation with the actuator piston. yA circular resilient seal 56 is secured as by bonding in a circular groove in the seal plate. These elements serve purposes which are hereinafter explained.

Cylindrical section 12, annular wall member 22, `and the orifice plate cooperate to define a rst pressure chamber or actuator chamber 5d. Cylindrical section 10, the actuator end wall and the orifice plate coopera-te to deine a second pressure chamber or accumulator chamber 6u. An appropriate connection 62 and a uid coupling 64 interconnect the actuator chamber with a source of pressure (not shown). A similar connection 66 and 3 coupling 68 connect the accumulator chamber with another source of pressure '(not shown).

An end portion 70 of the thrust column serves as a 1purnplplunger..Within a Abore 72 of .a pump1barrel-74. Pressurejsealing between the. p`lu1 n ger and the "barrel is provided l'by a resilient seal ring 76. The :pump `barrel "7'4 zis `coaxial with cylindricalV section '1'4 Vand 'has vits Vend portion threadedly secured in annular wallxnemberZ'Z. An enlarged threaded end portion "7'8 o`f amandrel` 80 is engaged' `in a 'threaded` portion or" `hore '72 of the-pump `barrel, 'as shown.

'flfrorn lthe )foregoing description, it `will be understood .thatthepumpbarrel and end pnrtion 78 ofthe-mandrel iieine a pump chamber 82. A seal LA'ring member 84 cooperates 'with "thepump kbarrel;*cylindrical vsection tl`4 tand annular wall memberf22 "in'dening Aa supply Acharn- -ber -86,vvli'nih is coaxial with thejpump chamber. Seal '88 on theseal ring membergprovidepressure sealing 'furthe chamber. `A'pa ssage"9'0 in the pumpasinginterfc'onnects the'two chambers foi-'the purpose vof Vvsupplying iiu'id to -the pump chamber.

In operation, the pressure `generator is -capable of very'rapidlyxproducing high pressure inthe pump charn- `ber. Ihernetho'd oi'accomplishin'g'thisthroughthe coaction of the orifice `plate '20, Vcircular resilient 'seal L56 and 'the iactuator'piston '44 'is Adiscussed in the co-pending Iappl'rcationi mentioned 1hereinbe`fore. It vis :briefly de- .'scr'ibed Lhereinrin orderto relatesit to A'the 'present invention `ivsetting 'pressure is introduced 'into `the Aactuator rdramberthrough fluid 'couplingfmtrom asource Vof pres- `sure (not shown). A -setting 'force `is thus produced Vwhich `seats the 'actuator piston -against circularresilient fseal '56 to velect 'positive pressure `sealing Ywhich isolates -chamberi5`8 from chamber 60. A high-actuatingpressure is introduced intoaccumulatorchamber60 through cougplingj. 'This 4pressure 'acts upon thearea of the piston `within seal 56 and is predetermined to balance the fforee o'f -t-he setting pressure 'acting upon the larger 'area on 'theopposite Vside` oflthejpiston. rPiston 44 is thus lheld lin equilibrium. The pressure in 'chamber 60 is then increased'by a pressure dilferential suicient'to unbalance thelforcesonthe'piston and causemovementof the piston from the oriiice plate. lSeal '56 is thereby disengaged 'and the high actuating pressure is thus released substantilly instantaneously upon the v'area of :the piston outside :circular-seal 56. --A 4great `net force Ais 'thus `-suddenly fexertedfonftheactuator pistonandfthe thrustfcolumn. The veircular seal vlis animportantelernent in the extremely 3rapid production of `this'high fforce, because `:it is adapted vfor 'sudden 'disengagement vfrom'the orilice iplateto releasetthe actuating pressure substantially instantaneously.

The veryrapidly produced Afhigh lthrust isftransla'tedby `plunger portion '70 `'of the thrustgcolumn into -a rapidly (generatedpressurein piunpchamber'.. The lproduction Lofhigh -pressureis aided Vby ahigh ratiorofactuatorpiston :area fto plunger area. :The fthrust-time i pattern produced onrthetln'ustcoliunn is vgoverned;by:selectionottl'teactuvating fand :setting `pressuresyas lvvell lfas by :the design Aof thepressure generator.

'From tthe iforegoingedescription, eit iwill be understood .that Vthe Jpressure-time .output pattern of the pressure generator may .be predetermined and .that the .rate tof .application of the output pressure may thereforebecontrolled Althoughgasniigiht be used in pump chambervjSZ, a 'liguidsuch as water is preferablyutilized 'The relative 'incompressibility of a liquid resultsfin very rapidproduction andltransmission of pressures. Itis assumed`here- 'ina'fter "that Water is utilized To prepare'thepressure generator for repeat operation, actuator p'iston '44 must be reseated `against the orilice plate .tore-establish pressure sealing between the piston and thepla'te by meansof resilient circular seal 156.

On`reseatingthe piston by reducing thepressurelin charnpressure approximating the reduced pressure is trapped between Athe ypiston andthe -orice plate by circular seal 56 and by seal 48. If the trapped pressure were not relieved, it would tend to oppose the force exerted by the setting pressure on the opposite side of the piston. To relieve the pressure, an opening 92 of very small diameter is provided in cylindricalfsection 12 adjacent to the orifice plate 4to .providermeansior automatically relieving the trapped pressure to the exterior atmosphere. The opening .is suiciently large Vto relieve strapped .pressure but -is not large enough .to .have-a significant etect'in releasing -t-he actuating pressure which passes `Jthroug'hthe oriiice to 'actuate .the piston.

In Figure 2 the tube-Haring apparatus is shown in detail. The enlarged .end portion 78 of mandrel 80 is secured in a threaded portion of bore 72 and extends axially through a circular opening 94 in end member it. An `axial opening 9.6 yin `the mandrel has an .enlarged ithreaded end portion in Whichiis .mounted a retainerQS. The retainer 'securesaspacer sleeve fagainst which' a shutoiifpin 162 is Vpositioned by the action of aheli'cal spring' 104. The mandrel is vprovided With radially extending passages 106 Ythrough whichthere is communication whenthe s 'hut-olpin moves 'from itspositi'on Ashown 'in'ligureZto the position shownin Figure.

An lannular seal memberlor seal Aconejlt Viss l it lably Nmounted on'the mandrel within an .enlarged opening 110 inhe endl portion of the pump :bai-rel. .A frustrolcon'ical Asurfacell'Z is provided for apurpose vvhich'will become clear -from discussion hereinafter. Sealing 4elements 1'14 are providedin appropriate grooves Lin the seal cone *to jprovide pressure sealing. 'A passage 116 `in the pump Abarrel interconnects pump chamber "82 and 'the opening H0 'in Ywhich the seal :cone -is positioned. Anadjustment 35 Vjneedle 'H 'is `threade'dly mounted Ain a `radial opening inthe pump barrel and extends into an elbow of passage '116, as shown, to provide means for selectively throttling the release of pressure against Lthe seal cone. Accessto the adjustment needle for a hand tool is provided 'bya port i120 in cylindrical -section Y'14.

' A tube spacer 122` lits `about the mandrel andis 'secured 'thereto by a bolt 12e. A sealing ring'provides pressuresealing between the-*mandrel-and the tube-spacer. The tube spacer and the mandrel `constitute mandrel means about l'which a tubel'ito V'beilared iispos'itioned clamping 'cone K134i is positioned about the tool ring.

As 'illustrated lin yFigures 4 'and 5, J'both the tool Vring Aand the clamping cone'areradiallysectioned 'and theretore adaptedor radial expansion Aand 'contraction 'about Lthe tube. The "clamping cone is re-tained 1argainst'axial movement yby 'a shoulder M2-on the tool ring and i'bya collar E34. A conoid'al'section 136 ,anda recessed irustro- 'conical wall .T933 are provided Jfor purposes "which -will become clear from discussion hereinafter. The collar .abuts end member l and encircles opening 94. :Dis-

posed about'the clamping `cone'is a-closing'conering 149, which `l1as an iinner frustro=conicalfsurface T42 `adapted for sliding engagement :with conoidal :section i136. ',flhe Vclosing cone ring, cylindrical "housingY section i4, end member i8 and collar '3.34 cooperatesto :define v:1t-pressure chamber '144, which "is interconnected by Lan appropriate .c onnectionlliti. and coupling 148`With uthe-source oltran- 'tuating'- pressure hereinbefore mentioned (not ishown). `Pressure .sealing forfthi's chamber 'isetiected by rappro Apria'fte sealing 'rings :disposed in rgrooves Lin the 'end-member and inthe closing coner'ing.

A ylindricalgspacer :15th maintains the 'closing cone ring 'inspaced rela-tion'with an opening cone ring `152, which Ihas Ya 'conicallportion i541 for sliding engagement with 'winner surface T42 nfthe el-arnpng cone. Theseafl fing Figures l and 5.

. tion of the tool ring, as shown in Figure 3. --action of the aring pressure in passage 116, surface 112 :the flaring operation. .'tube at a very high rate which is determined by the design of the particular pressure generator and by selection of the actuating and setting pressures.

From the -foregoing description, it will be understood :member 84 -is positioned .between cylindrical sectionl ,and the pump barrel, and is retained against axial movement by a shoulder on the pump casing. v

The seal ring member, the opening cone ring, the pump barrel and cylindrical section 14 together define a pressure chamber 156, to which the setting pressure is continuously supplied through an appropriate coupling 15S from the source of setting pressure hereinbefore mentioned. Sealing for the chamber is provided by annular l pressure seals in appropriate grooves in seal ring member Y the spacer.`

' In the operation of the tube-flaring machine, the tube 126 to be flared is inserted through opening 94 in end member 18 and is positioned about the mandrel means with the tool ring 12S and the clamping'cone in their vradially expanded or withdrawn positions, as shown in spacer until it contacts seal cone 168. By manipulation Vof control handle 42, the actuating pressure'is simultaneously lintroduced into the accumulator chamber 6G and into the pressure chamber 144 between end member 18 and the closing cone ring. The actuating pressure causes `the pressure generator to function in the manner described hereinbefore to very rapidly produce a high flaring pressure in pump chamber 82. At the same time, the actuating pressure in chamber 144 urges the closing cone ring `in a wedging action against the radially sectioned clamping cone. Being axially restrained between collar 131i and shoulder 132, the clamping cone 139 is radially contracted against tool ring 12S, which is also radially sectioned, and clamps it against the tube, as illustrated in Figures 2 and 4. The tube is thus clamped against the tube spacer to prevent axial movement during daring.

As the liaring pressure rises, it depresses the shut-off in4 102 against helical spring 1de, as shown in Figure 3. The pressure is thereby released through passages 166 in the mandrel into a chamber 164i defined by the `end portion of the tube, the mandrel, the tube spacer and the seal cone. The flaring pressure is simultaneously transmitted through passage 116 in the pump casing .and urges frustro-conical surface 112 of the seal cone `against the end of the tube, thereby effecting .dynamic sealing.

p The flaring pressure in chamber 16d flares the end portion of the tube outwardly against the contoured die por- Under the .of .the seal cone maintains continuous sealing contact with the tube during flaring. Loss of pressure between 1the tube and the seal cone is thus substantially prevented i and the flaring pressure is exerted on the tube throughout The pressure is -applied to the that the dynamic coaction effected by the present invention is such that the pressure which shapes a tube also effects dynamic sealing of the tube during shaping. it will also i be understood that tl e actuating pressure which activates l'the pressure generator simultaneously operates means `for clamping the tube during the shaping operation.

ln flaring the end porti-ou of a tube to an acute angle such as that illustrated in Figure 3, it is preferred that the seal conc exert only a sealing force and that it exert no substantial defonning or `liaring force. A flaring The tube is moved along the tubebe selected for shaping particular materials.

6 force exerted by the seal cone might tend to split the tube whenfadded to' the force of the daring pressure. The rate of release of pressure through passage 116 against the seal cone is adjustable by means of adjustment needle 118, in order to regulate the force exerted by the seal cone.

To remove the tube from the machine, control handle i2 is manipulated to relieve the actuating pressure in accumulator chamber 6i) and in chamber 144i. rl`he actuator piston is moved against the orifice plate by the setting pressure, `and the flaring pressure is thereby relieved. The :axial force on the closing cone ring 14d and the radial clamping force on the tool ring are relieved. The constant setting pressure in chamber 156 moves the opening cone ring 152 axially so that its conical portion 15d exerts a spreading action on recessed wall 154 of the clampingcone and expands its radial sections to :the coniiguration indicated in Figures 1 and 5. The closing cone ring is moved axially by the clamping cone to the position shown in Figure 1. The clamping force on the tube is thereby relieved and the Flared tube may be Withdrawn from the machine.

Upon the relieving of the flaring pressure, spring 1041 causes shut-off pin 162 to close radial passages 106 in the mandrel. This minimizes the amount of Water Which escapes through the drain opening 164) in spacer 15? when the tube is withdrawn, since the only Water which escapes is that in the chamber 164 dened by the tube, the mandrel, spacer 122 and the seal cone.

The anging of the end portion of a tube to an angle of is preferably accomplished in two stages. The tube is rst ared to an angle like that shown in Figure 3 in the manner hereinbefore described.

The tube is then inserted into a modied machine which utilizes the modied seal member 166 and the modified seal ring 168 shown in Figures 6 and 7. 1n the flanging operation it is desirable that the seal member exert sufficient orce on the tube to perform the last part of the daring operation. The force is adjusted by means of needle 118, which regulates the release of pressure through passage 116.

It is to be understood that the present invention may be utilized for shaping tube end portions into forms other than the ared and flanged configurations herein discussed.

As discussed hereinbefore, the present invention is capable of applying shaping pressure to a tube at a high predetermined rate. Optimum pressures and rates may The high pressures obtainable with the pressure generator hereinbefore described make possible the shaping of relatively heavy tube walls, the shaping of which has heretofore been substantially impracticable. The capability of shaping material at a high optimum rate minimizes work hard ening and stress concentration. Tube damage and failures during the shaping operation and in service are therefore minimized. This is of great importance with respect to materials such as stainless steel which are particularly subject to damage caused by stress concentration and Work hardening.

For selecting the rate of application of shaping pressure, the adjustment means described and claimed in the copending application hereinbefore mentioned, may be `utilized. By this means the rate at which pressure is applied may be varied by a convenient mechanical adjust- 'ment Without altering the input pressures. which operate the pressure generator.

Although specic embodiment ofthe present invention has been described and illust-rated in detail, it is to be clearly understood that the same is by way of illustration only; it is to be understood that the invention is not limited thereto, as many variations will be readily apparent to those versed in the art and the invention is to be given its broadest possible interpretation within the terms of the appended claims.

assume tube, a radially .sectioned .tool y'ringhaving acontoured portion and adapted for radial expansion and contraction .about the tube, .means responsive tof-said actu-atingfpressure for contracting the tool `ring about the'tuhefto secure the tubeagainstfsaid mandrel means, afsealmemberhav- .ing a back surface and a front surface with l.a .surfaceportion of lesser area .than the area of said back surface,.said surface portion confronting said end .portion of the tube, means for applying the shaping.pressuretosaid tback-surface to urge .said surface portion against saidend portion to cooperate therewith and with .said .mandrel meansto vdefine a pressure chamber, .and .means for introducing the shaping pressure into said .pressure .chamberysaid seal .member retaining the daring `.pr.e.ss.ure..within said .chamber while said end portion of the tube is shaped .against said contoured portion .by said pressure.

2. An apparatus for shaping theend portion ofaltube comprising -a pump chamber, plunger meansslidablyipositioned in the pump chamber, cylinder means, .an .actuator piston slidably positionedfin the .cylinder zmeansnd .Connected with the plungermeans, ayplateconfronting .said actuator piston and .deningan orifice, sealing .means `diS- Aposed between the actnatorpiston and the-,plate foreffectingepressure sealing therebetween about theoriiice, means `for exerting a setting force urging said actuator piston Ytoward the plate to cover the orifice and .effect said/.pressure sealing, and means forestablishing anactuating pressure to act upon a portion of the actuator-piston .within the sealing means to overbalance the'settingforceand expose .an increased area .of the actuatorpiston.totheactuating pressure, whereby thrust is exerted on saidplunger. means Vto produce a shaping pressure in said pump chamber, mandrel means for mounting said tube, sea'l means .having a 'back surface and a front surface with asur'face portion of 'lesser area than the area of saidback surface,.means .for .applying the shaping pressure to said backsurface ;to .urge said surface portion against said tube end portion to .cooperate therewith and with said mandrel means .tor define a pressure chamber, means for introducing the -shaping 4pressure within said pressure chamber7 and lmeans respon- 'sive to said actuating pressure for clamping said Vtube against said mandrel means, wherebythe end portion of 4the tube is shaped.

'3. An apparatus for shaping the end `portion .o'fatube zcompris'ingrmeans defining an -actuator chamber .anda pump chamber, a plate defining an orifice at an vend .of said actuator chamber, an actuator piston positioned within said actuator chamber and confronting the plate, plunger means connected with said .actuator piston and .slidably positioned in said purnp chamber, sealing .means positioned between the actuator `piston and the plate .for V,effecting pressure sealing therebetween about the orifice, means `for `exerting a setting Vforce urging the piston .toward-the plate to covertthe orifice and effect said pressure sealing, and vmeans for establishing an actuating pressure to act upon a portion ofthe actuator piston withinisaid sealing means. to overbalance ,saidforce and 'expose an increased area of the actuatorpiston totheactuating pressure, Vwhereby .thrust is exerted on said plunger means to vproduce a shapingpressure insa'dpump chamber, .man-

drel means for mounting said tube, a radially .sectioned tool ring .adapted lfor radial expansion and contraction about the tube, means responsive *to said Vactuating pressure for contracting the tool ring about the'tube tosecu-re thetube against said mandrel means, aseal memberhaving a back surface'anda-front'surface with-a surface por- `tion of lesser area than the 'area-ofjsaidback surface, said surface portionconfronting said end portion of the tube, Vmeans for applying the shapingzpressure tor-said back-surface tourge saidsurface vportion against said end portion :to cooperate therewith .and with said ymandrel .means sto dene a pressure chamber, .and @passage trneans vinterconval() meeting esaidpresaure :chamber :withfsaid pump chamber, ewhereby :saidttuhe endmortionis .shaped bysaidfshaping pressure. Y i

r4. fAn apparatus for .fshapiug .the :end iportionfofa tube .comprisingmeans for generating a' ihigh shaping ipressure, .mandrel fmeans extending :into the .tube fortmountingaid .tu-be, aseal member having a hack suifacepand aront surface `with a .surfaceportion-,of Vlesser area than theeareal -osaid backsurface, .means `forapplying the :shapingfpressure .toesaid shack surface to urge said surfaceV p ortion against a'n end portion of the tube to cooperate therewith .and with said .mandreljneansio `define .a pressure chamyber,v said mandrelrneanshaving passage means intercon- 1. necting said pressure chamber .and .saidpressuregenerat- ,ing.1neans., a tool `ring 4coaxial with .the.-n1andrel` means .and radially vsectioned .for .contraction against .s aid .-tube, .said tool .ring having a contouredportionpositioned.abopt .said Atubeend portion, vand means for .contracting .said .tool ring to secure the tube against the mandrel means, .where- .by-.said end YAportion .of .the .tubeis radiallyformed against .said contoured portion vof the .tool ring by the shaping pressure.

5. An .apparatus .for shaping the .end portion .of aatu'be vvcomprising meansfor generating aln'gh shaping pressure, mandrel means .for mounting the tube, laseal merber .having -a .back surface anda front surface witha surface portion'o'f lesserarea than .the area of said back surface, said surface .portion confronting said end portion of said tube,f means for applying the shaping pressure to salid back surface to urge ,said surfaceportion against'theltu'be tocooperate Atherewith and withsaid mandrel means to define a ypressure' cham-ber, said mandrel means-defining .passage means interconnecting .said chamber 'and Asaid pressure generating means, a .tool ring coaxial with `the mandrel means and radially sectioned for contraction about the tube, saidtool ring'havinga 'contoured portion positioned about said end portion of the tube, afclamping 1cone coaxial with .the '.tool nring and radiallysectionedfor contraction thereabouna closing cone 'ring adapted-to be urged kby `an axial force against the clamping conerinfa wedging `action to contract the clamping cone 'about -said tool `ring V.to secure'the tube against said-mandrelfmeans, and rneans for `exertingsaid'axialiforce on theclosing-cone ring, whereby 4the end portion of the ytube is `radially 'formed against said Vcontoured `portion ofthetool'ringjby `the vshaping pressure. l 6. An apparatus Vforshaping an end'portion'of atub 4comprising a pump chamber, `plunger means slidably positioned inthe pump chamber, cylinder means, an actuator piston slidably/positioned 'in the cylinder lmeans and lconnected with the plunger means, a plate confronting `said actuator piston and defining an orifice, sealing means^disposed between the actuator piston and the plate forA effecting pressure 'sealing' therebetween about fthe orifice, -means .forl'exertinga setting forceurging said actuatorpistonztoward the'plate to cover .the orifice'and eifect'said pressure sealing, Yand `means for vestablishing f an 4actuating pressure to Aact upon -a portion of the\actuator piston within-the 'sealing means to voverbalance the-settingforce and'expose Aan increased yarea -of the actuator piston to the actuating pressure, whereby thrust is exerted on vsaid plungermeans to produce a shaping pressure in said vpump chamber, mandrel means for mounting .the tube, Aa seal :member;having a back surface and` a frontsurfacewith a-fsurface por'- 4tion of lesser area thantheareafof-saidback surface, said :surface :portion confronting said endl portion .ofsaid tube, means :for applying'thetshaping pressure to said back;sur '.face ;to urge .said .surface .portion .against the Ytube to cooperate therewith andwithsaidmandrel means-.todeiine a .pressure chamber, said mandrel means defining .passage means .interconnecting said pressure chamber and said pump chambena vtoolring-coaxial with the. mandrel means and .radially-sectioned for contraction about the tube, said tool rling .haring Va contoured portion 4positioned about :said riendportion 'of-the ztube, a clamping-coneringvadapted to be urged by an axial force against the clamping cone in a wedging action to contract the clamping cone about said tool ring to secure the tube against said mandrel means, and means for exerting said axial force on the closing cone ring, whereby `the end portion of the tube is radially formed against said contoured portion of the tool ring by the shaping pressure.

7. Apparatus for shaping the end portion of a tube comprising means for generating a high shaping pressure, mandrel means tting within the tube for mounting said tube, a seal member having a back surface and a front surface with a surface portion of lesser area than the area of said back surface, said surface portion confronting said end portion of the tube, means for applying the shaping pressure to said back surface to urge said surface portion against the tube to cooperate therewith and with said mandrel means to define a pressure chamber, said mandrel mea'ns dening passage means interconnecting said chamber and said pressure generating means, a tool ring coaxial with the mandrel means and radially sectioned for contraction about the tube, a radially sectioned clamping cone coaxial with the ma'ndrel means, said clamping cone having a conoidal section and a recessed frustro-conical wall, a slidably mounted closing cone ring adapted to engage said conoidal section to produce a wedging action on the clamping cone, means for urging the closing cone ring in said wedging action to contract said tool ring and secure the tube against the mandrel means, a slidably mounted opening cone ring having a conical portion adapted to engage said recessed wall in a spreading action to release the tube, and means for actuating the opening cone ring to effect said spreading action, whereby the end portion of the tube is radially formed against said tool ring and lreleased thereafter.

8. An apparatus for aring the end portion of a tube comprising means defining an actuator chamber and an accumulator chamber, a plate defining an orifice between said chambers, an actuator piston positioned in said actuator chamber and confronting the plate, sealing means positioned between the actuator piston and the plate for effecting pressure sealing therebetween about said orifice, means for establishing a setting pressure in the actuator chamber to exert a force urging the piston toward the plate to cover the orifice and effect said pressure sealing, means for establishing in the said accumulator chamber an actuating pressure to act upon a portion of said actuator piston within the sealing means to overbalance said force and expose an increased area of the actuator piston to the actuating pressure for producing a shaping pressure in said pump chamber, mandrel means for mounting the tube, a seal member having a Kback surface and a front surface with a surface portion of lesser area than the area of said back surface, said surface portion confronting said end portion of the tube, means for `applying the shaping pressure to said back surface to urge said surface portion against the tube to cooperate therewith and with said mandrel means to define a pressure chamber, said mandrel means dening passage means interconnecting said pressure chamber and said pump chamber, a tool ring coaxial with the mandrel means and radially sectioned for contraction about the tube, a radially sectioned clamping cone coaxial with the mandrel means, said clamping cone having a conoidal section and a recessed frustro-conical wall, a slidably mounted closing cone ring adapted to engage said conoidal section to produce a wedging action on the clamping cone, means for applying said actuating pressure to the closing cone ring in said wedging action, to contract said tool ring and secure the tube against the mandrel means, a slidably mounted opening cone ring having a conical portion adapted -to engage said recessed wall in a spreading action to release the tube, and means for exerting said setting pressure on the opening cone ring to effect said spreading action, whereby the end portion i of the tube is radially formed against the tool ring and re leased thereafter.

References Cited in the le of this patent UNITED STATES PATENTS 989,805 Reynolds Apr. 18, 1911 1,930,745 Fisher Oct. 17, 1933 2,100,092 Tear Nov. 23, 1937 2,453,785 Cousino Nov. 16, 1948 2,464,510 Hull Mar. 15, 1949 2,667,841 Meader Feb. 2, 1954 2,713,314 Leuthesser Iuly 19, 1955 

